SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '603932c6612589dfc0ce516e1b3800d924fbe7c287307d55d2c2b7f54f55719d' 
  AND token = 'm+iUUvyokDf4nOTBcKCl+P+K6vGWI3hR0V2zun4eYfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}